Molar Volume of a Gas at STP

So...you guys all must be wondering what STP stands for. Well.... I'll tell you what it stands for because I'm such a genius! STP stands for...Standard Temperature and Pressure.

We use STP as a standard condition  to compare different sets of data, ( in our case, comparing the volume of gases). STP is most commonly used to measure gas density and volume.

The STP also corresponds to 1 atmosphere of pressure and a temperature of 0° or 273.15K. gases change in size as they expand and contract when the volume changes in temperature and pressure. We use the STP to study or test a chemical.

At STP there is 22.4 L per one mole.

With this information, we can create the conversion factor:

22.4 L of gas                                                1 mole of gas
1 mole of gas          OR switched around...    22.4 L of gas

Add caption

*This is for you to help visualize the formula.

*This is just another picture to help visualize what is going on. Because the cube has a volume of 22.4 L , so there is only 1 mole of Gas at STP











So... now for some examples...

example 1/ Calculate the volume occupied by Br2O  at STP!

Step 1 : Br20 has a molar mass of  175.8 grams
Step 2 : Convert it to moles, in order to apply it to the formula



175.8 grams  x 1 mole Br20         = 1.83 moles ( remember your sig figs!)
                        95.9 grams

Step 3:  multiply the moles with the equation we just learned!!!

1.83 moles x  22.4 L of gas    = 41.0 L of gas
                      1 mole of gas


AND BAM that is your answer! Easy eh? Well if you still don't get it... Well watch this video! Because I stink at explaining anyways :)





Now you know all about STP? well.. you should try these practice problems before you think you're all that. Cuz....who knows, STP might be harder than you think it is!

http://jc-schools.net/dynamic/science/worksheets/MolarVolumeSTPPractice.pdf

HAVE FUN!